A GaP/morin nanocomposite material was prepared, and the key factors affecting the luminescent properties of the material were investigated. Intense luminescence was observed after the composite reaction between GaP nanocrystals and morin. The luminescence of the GaP/morin composite material is intensified remarkably with the ratio ofmorin to GaP nanocrystals increasing, but the peak wavelength remains unchanged. With the size of GaP particles decreasing, the luminescent intensity of the composite increases and the peak wavelength blue-shifts. The possible reason for this phenomenon was discussed.